While not intended to be so limited, the tool and method of the present invention are particularly well adapted for use in light gage steel framing for residential and commercial buildings. An example of another use for the tool and method of the present invention is the assembly of trusses and the like.
Today, most light gauge steel framing for residential and commercial buildings is done with an electric screw driving tool using self-drilling and tapping screws. The parts to be joined together are manually held in place while the screw is driven. Screws are easily dropped and lost. The use of the tool and method of the present invention provides a more flush surface on which to apply dry wall. The method of the present invention is easier than the use of self-tapping screws and is less time consuming. The staple driving tool clamps the metal framing members together prior to stapling and, if necessary, this clamping can be readjusted prior to stapling. Staples are cheaper than screws and are self contained in strips or "sticks". Thus, staple loss and waste is much lower than with screws. The staple driving tool is provided with a safety and the clamping mechanism is actuated either by the safety or by the manual trigger of the tool.
As indicated above, in the typical prior art light gauge steel framing techniques employed, the individually hand driven self-tapping, screws are driven with the aid of an electric screw driver. This approach is time consuming. Pneumatically driven steel framing pins have also been used, but it has been found that pins generally do not perform as well as screws in cyclic loading conditions. The present invention will allow for forced entry fastener installation using electric or pneumatic tools, not effected by vibration or cyclic loading to the extent that typical forced entry framing pins are. Another advantage of the present invention is the reduction in cost of assembly when using light gauge steel framing members.
The pivotal clamping jaw, the link, the toggle elements and the air cylinder of the present invention, to be described hereinafter, are affixed to a mounting bar which extends along and beneath the tool magazine. This assembly may be applied (with minor modification) to a number of existing staple driving tools. In FIG. 1 to be discussed hereinafter, this mechanism is shown affixed to a staple driving tool manufactured by Senco Corporation of Cincinnati, Ohio and sold under the designation SNS-45.